Here is the answer to your question
Answer:

Explanation:
From the question we are told that:
Crane Length 
Crane Mass 
Arm extension at lifting end 
Arm extension at counter weight end 
Load 
Generally the equation for Torque Balance is mathematically given by



Answer:
A star with 15 solar masses is too big to be a main-sequence star.
Because the more advances made in the world means the more we can learn on how things work and how we can better the lives of humans and other species. If we didn't have scientific advancements we wouldn't have cell phones, electric, tv, car, computers, ect. We would still be living in Cave man era with clubs and horrible language skills.
Answer:
Chemical bonds
Explanation:
The chemical bonds hold the different type atoms or ions together.
The type of chemical bonds :
1. Ionic bond ;
Ions or atoms changes the electron and form ionic bond.Those atoms gains the electron gets negative charge and those atoms donate the electron gets positive charge.
2.Covalent bond :
In this type of bond atoms share the electrons and form covalent bonds.
3. Metallic bond :
This type of bond are present in the metals.In this atoms are used free electrons to form bonds.
Therefore answer is --
Chemical bonds